21304055531 has 8 divisors (see below), whose sum is σ = 23534976000. Its totient is φ = 19122166440.

The previous prime is 21304055527. The next prime is 21304055537. The reversal of 21304055531 is 13555040312.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 21304055531 - 2² = 21304055527 is a prime.

It is a super-3 number, since 3×21304055531³ (a number of 32 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21304055494 and 21304055503.

It is not an unprimeable number, because it can be changed into a prime (21304055537) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 12256931 + ... + 12258668.

It is an arithmetic number, because the mean of its divisors is an integer number (2941872000).

Almost surely, 2^21304055531 is an apocalyptic number.

21304055531 is a deficient number, since it is larger than the sum of its proper divisors (2230920469).

21304055531 is a wasteful number, since it uses less digits than its factorization.

21304055531 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 24515689.

The product of its (nonzero) digits is 9000, while the sum is 29.

Adding to 21304055531 its reverse (13555040312), we get a palindrome (34859095843).

The spelling of 21304055531 in words is "twenty-one billion, three hundred four million, fifty-five thousand, five hundred thirty-one".